1. Field of Invention
The present invention relates to a control knob for a vehicle, and more particularly, to a control knob for a vehicle, with an improved outward appearance.
2. Description of Related Art
In general, a vehicle is equipped with a shift lever to select each gear. Further, when the shift lever is manipulated by a driver, a selecting cable and a shifting cable connected to the bottom of the shift lever are moved in connection to perform selecting and shifting of gears.
A control knob is installed on the shift lever. Here, the control knob denotes a handgrip installed on the end of the shift lever. Further, the control knob is formed to improve the grip feel of the shift lever. Moreover, as a decorative element inside a vehicle, the outward appearance of a control knob is important.
A control knob may be produced by applying dual injection molding according to the intent of the producer. Here, dual injection molding is a forming method in which two materials are used to produce an integrally and/or monolithically formed item. In such dual injection molding, a mold designed to be capable of dual injection molding is used which uses an injection molding machine with a structure in which two injection molding devices, a rotating device installed on a moving plate, and a core or a slide structure are used. Further, one material is injected in a primary cavity, and another material is injected into a secondary cavity to produce a formed item in which two materials are integrally formed.
In dual injection molding, because the primary cavity and the secondary cavity are precisely replaced, there are few restrictions as to the shape and the range of products to which the process may be applied. As described above, two materials are simultaneously extruded in dual injection molding. Accordingly, costs may be reduced and designs may be diversified when compared to a related art forming method which requires that two components are formed through two extrusion processes, followed by secondary processing such as bonding or painting.
However, for a control knob produced by dual injection molding, a boundary line may be formed between two different materials or an abrupt change in color may occur, which may deteriorate the outward appearance of the control knob.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.